The EPA requirement for a landfill liner barrier is <10-7 cm/sec. Lime-stabilized clayey soils, when treated with proper amounts of lime and water, mixed, cured and compacted, can exhibit hydraulic conductivity (or permeability) values in the order of 10-6 - 10-8 cm/sec., or roughly the same as 10 times that of a compacted clay impermeability barrier. This, combined with the improved strength of lime-stabilized clayey soil, is equivalent to or superior to that of an asphalt-impregnated geosynthetic fabric moisture barrier.
Clay-bearing soils stabilized with lime and silty soils stabilized with lime-pozzolan mixtures exhibit markedly different properties than the starting materials. As a consequence, the stabilized materials find wide use in construction. It is commonly more economical to upgrade the physical properties of the in-situ materials than to excavate and replace the native materials with imported construction base materials.
A construction base material should perform as a permeability barrier. Permeability is defined as the measure of the flow of water through soil. The ease (or measurable rate with which gasses, liquids, or plant roots penetrate or pass through a layer of soil or porous media. The capacity or ability of a porous rock, sediment, or soil to allow the movement of water through its pores.
To achieve low permeability, the voids and pore spaces in a material should be minimized or filled. A compacted clay has a low permeability, but lacks the other desirable properties of a suitable construction base - compressive strength and durability.
Lime stabilization brings improved strength and durability without sacrificing much of the impermeability associated with clays.
BENEFITS TO BUILDING PAD CONSTRUCTION
-Treatment eliminates the shrink/swell potential of clayey soils, which reduces future foundation problems.
-A treated building pad creates an impervious moisture barrier, which eliminates future floor wetness.
-Winterizes the building pad, eliminating the effects of rain saturation and expedites the construction schedule. Treatment increases the strength